It’s been ages since I posted my last entry here. I missed this blog so much.
I’ve been really busy doing and organizing a lot of stuff during the last couple of months that I rarely had time to write. Moreover, the observing conditions were very seldom good because of the rainy season – several typhoons hit the country and it’s too cloudy most of the time.
It is not until towards the end of September that the rainy season in the Philippines will start receding. Its normal termination usually occurs by the end of October.
Anyhow, the coming of October also marks the coming of longer nights in the Philippines. Just last October 1, the Sun rose at 5:46 AM and set at 5:46 PM (Manila time). This day signaled the transition point in nature when the light changes. The days are getting shorter in the Northern Hemisphere — everyone can feel the shortening of the days and sense, innately, that the changes in daylight and darkness are sudden and surprising.
During the equinox last September 23, the length of night and day across the world is nearly, but not entirely, equal. This is because the day is slightly longer in places that are further away from the equator, and because the sun takes longer to rise and set in these locations. The axial tilt of the earth affects the day/night duty cycle most strongly at the poles and has no effect at all at the equator. Equal day and night usually occurs a few days after the equinox. For simplicity, we may assume that it has actually occurred on October 1. Take note that there is really no equal day and night at the equator.
For amateur astronomers, longer nights mean extra hours of uninterrupted stargazing!
The fine meteor showers usually come in by October to December of each year. October 2011 has two meteor showers worth getting outside to see — the Draconid meteor shower on the evenings of October 7 and 8 and the more reliable Orionid meteor shower on the mornings of October 20 and 21.
As the Draconids and Orionids kicks off the meteor shower season, observing the night sky would be more fun and interesting.
Clear skies to all!
Before I forgot… Happy Equinox, everyone!
The word “equinox” derives from the Latin words meaning “equal night” and refers to the time when the sun crosses the equator. At such times, day and night are of nearly equal length everywhere in the world.
While the March equinox marks the beginning of spring in the northern hemisphere, it is the start of autumn in many parts of the southern hemisphere.
During the equinox, the length of night and day across the world is nearly, but not entirely, equal. This is because the day is slightly longer in places that are further away from the equator, and because the sun takes longer to rise and set in these locations. Furthermore, the sun takes longer to rise and set farther from the equator because it does not set straight down – it moves in a horizontal direction.
Moreover, there is an atmospheric refraction that causes the sun’s disk to appear higher in the sky than it would if earth had no atmosphere.
How high the Sun gets in your sky, and how long it is above the horizon during the day, depend not only on the season, but also on your latitude.
2011 promises to be a great year for astronomy enthusiasts as it was filled with several upcoming spectacular lunar and solar eclipses, beautiful planetary conjunctions, celestial groupings and of course, annual meteor showers.
What excites me most about this year is that all of Asia including the Philippines — where I live — will be able to see all of the eclipse phases of a Total Lunar Eclipse on December 10, 2011, including a “Reddish Moon” during the peak stage. Such is truly a rare event to witness, but how rare is that? Well, according to what I found during my online research, I think the last total lunar eclipse that was visible from the Philippines occurred during the 1980s. I wasn’t even alive then.
Anyway, below is a list of astronomical events for this year (arranged according to date) to serve as a guide on your skygazing and give you a preview on your 2011 cosmic journey.
|January 3 – 4||Quadrantid Meteor Shower peaks The Quadrantids are an above average shower, with up to 40 meteors per hour at their peak. The shower usually peaks on January 3 & 4, but some meteors can be visible from January 1 – 5. Best viewing will be from a dark location after midnight. Look for meteors radiating from the constellation Bootes.|
|January 4||Partial Solar Eclipse The partial eclipse will be visible in most parts of northern Africa, Europe, and Asia. (NASA Map and Eclipse Information)|
|January 10||Crescent Moon and Jupiter approximately 10 degrees apart.|
|March 20||Equinox The March Equinox occurs at 23:21 UTC. The Sun will shine directly on the equator and there will be nearly equal amounts of day and night throughout the world. This is also the first day of spring (vernal equinox) in the northern hemisphere and the first day of fall (autumnal equinox) in the southern hemisphere.|
|April 3||Saturn at Opposition|
|April 22 -23||Lyrid Meteor Shower peaks The Lyrids are an average shower, usually producing about 20 meteors per hour at their peak. These meteors can produce bright dust trails that last for several seconds. The shower usually peaks on April 21 & 22, although some meteors can be visible from April 16 – 25. This year, the gibbous moon will hide most of the fainter meteors in its glare. Look for meteors radiating from the constellation of Lyra after midnight, and be sure to find a dark viewing location far from city lights.|
|May 5 – 6||Eta Aquarid Meteor Shower peaks Eta Aquarids Meteor Shower. The Eta Aquarids are a light shower, usually producing about 10 meteors per hour at their peak. The shower’s peak usually occurs on May 5 & 6, however viewing should be good on any morning from May 4 – 7. The radiant point for this shower will be in the constellation Aquarius. Best viewing is usually to the east after midnight.|
|March 15||Mars-Jupiter Conjunction Like two ships passing in the twilight, Mercury and Jupiter come within 2 degrees of each other this evening. For comparison, your fist held at arm’s length covers about 10 degrees of arc in the night sky.Jupiter will be heading toward the sun, while Mercury is moving away from the sun during this time. Immediately after sunset, concentrate on that part of the sky just above and to the left of where the sun has just set. Using binoculars, sweep around this part of the sky to see bright Jupiter sitting just below and to the left of the harder-to-spot Mercury.|
|May 11 (all month long)||Four of the five naked-eye planets will crowd together into what could be described as a Great Celestial Summit Meeting.Mercury, Venus, Mars and Jupiter are contained within a 10-degree span on May 1, shrinking to a minimum of less than 6 degrees on May 12, then opening back up to 10 degrees on May 20.Twice during May, three planets close to within nearly 2 degrees of each other: Mercury-Venus-Jupiter (on May 11-12) and Mercury-Venus-Mars (May 21). And the crescent moon joins the array on May 1 and again on May 30-31.|
|June 1||Partial Solar Eclipse The partial eclipse will be visible in most parts eastern Asia, Alaska, northern Canada, and Greenland. (NASA Map and Eclipse Information)|
|June 15||Total Lunar Eclipse The eclipse will be visible throughout most of South America, Europe, Africa, Asia, and Australia.(NASA Map and Eclipse Information)|
|June 21June 23- 27||June SolsticeOccurs at 17:16 UTC. The North Pole of the earth will be tilted toward the Sun, which will have reached its northernmost position in the sky and will be directly over the Tropic of Cancer at 23.44 degrees north latitude. This is the first day of summer (summer solstice) in the northern hemisphere and the first day of winter (winter solstice) in the southern hemisphere.Pluto+Charon+Hydra occultation by 2 bright starsRead more …Link 1, Link 2, Link 3|
|July 1||Partial Solar EclipseThis partial eclipse will only be visible off the coast of Antarctica. (NASA Map and Eclipse Information)|
|July 28 -29||Southern Delta Aquarid Meteor Shower The Delta Aquarids can produce about 20 meteors per hour at their peak. The shower usually peaks on July 28 & 29, but some meteors can also be seen from July 18 – August 18. The radiant point for this shower will be in the constellation Aquarius. This year the thin, crescent moon will be hanging around for the show, but it shouldn’t cause too many problems. Best viewing is usually to the east after midnight from a dark location.|
|August 12 -13||Perseid Meteor Shower The Perseids is one of the best meteor showers to observe, producing up to 60 meteors per hour at their peak. The shower’s peak usually occurs on August 13 & 14, but you may be able to see some meteors any time from July 23 – August 22. The radiant point for this shower will be in the constellation Perseus. Look to the northeast after midnight.|
|August 22||Neptune at Opposition The blue planet will be at its closest approach to Earth. This is the best time to view Neptune, although it will only appear as a tiny blue dot in all but the most powerful telescopes.|
|September 23||Equinox The September equinox occurs at 09:05 UTC. The Sun will shine directly on the equator and there will be nearly equal amounts of day and night throughout the world. This is also the first day of fall (autumnal equinox) in the northern hemisphere and the first day of spring (vernal equinox) in the southern hemisphere.|
|September 25||Uranus at Opposition The blue-green planet will be at its closest approach to Earth. This is the best time to view Uranus, although it will only appear as a tiny blue-green dot in all but the most powerful telescopes.|
|October 8||Draconid Meteor Shower Many meteor experts are predicting a good chance that an outburst of up to many hundreds of Draconid meteors will take place. Unfortunately, like the Perseids, a bright moon could severely hamper visibility. The peak of the display is due sometime between 16h and 21h UT, meaning that the best chances of seeing any enhanced activity from these very slow-moving meteors would be from Eastern Europe and Asia.|
|November 10||Mars and bright star A colorful conjunction takes place high in the predawn sky between the yellow-orange Mars and the bluish-white star Regulus in Leo, the Lion. They are separated by 1.3 degrees, but they’ll be within 2 degrees of each other for five days and within 5 degrees of each other for nearly three weeks, so they will be a rather long-enduring feature of the mid-autumn morning sky.|
|October 21-22||Orionids Meteor Shower The Orionids is an average shower producing about 20 meteors per hour at their peak. This shower usually peaks on the 21st, but it is highly irregular. A good show could be experienced on any morning from October 20 – 24, and some meteors may be seen any time from October 17 – 25. Best viewing will be to the east after midnight.|
|October 29||Jupiter at Opposition The giant planet will be at its closest approach to Earth. This is the best time to view and photograph Jupiter and its moons.|
|November 17 -18||Leonids Meteor Shower The Leonids is one of the better meteor showers to observe, producing an average of 40 meteors per hour at their peak. The shower itself has a cyclic peak year every 33 years where hundreds of meteors can be seen each hour. The last of these occurred in 2001. The shower usually peaks on November 17 & 18, but you may see some meteors from November 13 – 20. Look for the shower radiating from the constellation Leo after midnight.|
|November 25||Partial Solar Eclipse This partial eclipse will only be visible over Antarctica and parts of South Africa and Tasmania. (NASA Map and Eclipse Information | NASA Eclipse Animation)|
|December 10||Total Lunar Eclipse The eclipse will be visible throughout most of Europe, eastern Africa, Asia, Australia, the Pacific Ocean, and the North America. ((NASA Eclipse Information)|
|December 13 – 14||Geminids Meteor Shower Considered by many to be the best meteor shower in the heavens, the Geminids are known for producing up to 60 multicolored meteors per hour at their peak. The peak of the shower usually occurs around December 13 & 14, although some meteors should be visible from December 6 – 19. The radiant point for this shower will be in the constellation Gemini. Best viewing is usually to the east after midnight.|
|December 21||December Solstice The December solstice occurs 05:30 UTC. The South Pole of the earth will be tilted toward the Sun, which will have reached its northernmost position in the sky and will be directly over the Tropic of Capricorn at 23.44 degrees south latitude. This is the first day of winter (winter solstice) in the northern hemisphere and the first day of summer (summer solstice) in the southern hemisphere.|
Clear skies and happy skygazing!
SPACE.com – Solar Eclipse and Meteor Shower to Launch 2011 Skywatching Season
AstronomyOnline.org — Dates for conjunctions, eclipses, meteor showers and transits
Wondering what’s that big bright star that was visible all night? It was the planet Jupiter, and it’s far brighter than any true star in the night sky. Jupiter can already be seen twinkling low in the east after twilight, and higher in the southeast as the evening wears on.
Even the skies seemed to be cloudy at night here in the Philippines, Jupiter often still stands out amidst the dark sky.
This giant gas planet is always bright, but it shines brighter this month. On the 21st (8PM PST), Jupiter will swing closer to Earth (368 million miles away) and shine brighter than at any time between 1963 and 2022 . It will remain nearly this close and bright (magnitude -2.9) throughout the second half of September.
The night of its closest approach is also called “the night of opposition” because Jupiter will be opposite the sun, rising at sunset and soaring overhead at midnight. This opposition is special because Jupiter, the largest of all the solar system’s planets, will soon reach perihelion, the closest point in its orbit to the Sun. That means it’s physically closer to Earth during this opposition than a normal one. It will rise below the Circlet asterism in the constellation Pisces the Fish and present its best views high in the sky, when its light travels through less of Earth’s atmosphere.
Because Jupiter is so close to Earth, this is a great opportunity to view it through a telescope. Jupiter is most interesting when the Gred Red Spot is visible and/or when one of the moons is casting a shadow on Jupiter’s disk.
Happy sky viewing!
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Fast facts about Jupiter
- Jupiter is the largest planet in the solar system. More than 1,000 Earths could fit inside Jupiter, and all the other planets together make up only about 70 percent of Jupiter’s volume.
- It takes Jupiter about 12 years to orbit the Sun once, but only about 10 hours to rotate completely, making it the fastest-spinning of all the solar system’s planets.
- Jupiter rotates so rapidly that its polar diameter, 41,600 miles (66,900 kilometers), is only 93 percent of its equatorial diameter, 44,400 miles (71,500 km).
- Jupiter reflects 52 percent of the sunlight falling on it, more than any other planet except Venus (65 percent).
- Jupiter’s four bright moons, Io, Europa, Ganymede, and Callisto, are easily visible through small telescopes. Io takes less than 2 days to orbit, so its relative position visibly changes in an hour or so — less when it appears close to Jupiter.
- Our line of sight lies in the plane of the jovian moons’ orbits, so we see occultations (when a moon moves behind Jupiter), eclipses (when Jupiter’s shadow falls on a moon), and transits (when a moon passes in front of Jupiter) at various times.
- Jupiter’s moon Ganymede is the solar system’s largest satellite, with a diameter of nearly 3,300 miles (5,300 km), greater than that of Mercury.
sources: SkyandTelescope.com, Spacedaily.com, Astronomy.com
* Venus, Mars and Spica together in evening sky at start of month * The above 3 joined by the Moon on the 11th * Jupiter at opposition (21st) with Full Moon (23rd) and Uranus nearby * Mercury bright in the morning sky
Western sky view a few minutes after sunset on September 11 – the thin crescent moon joins the celestial trio of Venus, Mars and Spica (brightest star of Virgo)
Philippine nights will be longer as the Sun approaches the celestial equator. Autumnal equinox will occur on September 23 when day and night will have approximately equal length on Earth.This point is also called as First point of Libra.
The rich band of constellations and stars along the Milky Way from the constellations Cygnus, the Swan, in the north to Sagittarius and Scorpius in the south, begin to give way this month to fainter constellations, many of them with watery associations such as the constellations of Capricornus, the Sea Goat, Aquarius, the Water Bearer and Pisces the Fish. The famous asterism Teapot in the sky in the constellation of Sagittarius can be observed at about 40 to 47 degrees above the southern horizon, an hour after sunset as shown below.
Betelgeuse, the super giant red star and the prominent star of the famous constellation Orion, the Mighty Hunter, will be located at about 25 degrees to the upper right of Mars. Sirius, the brightest star in the sky of the constellation Canis Major, the Big Dog, will be an easy target as it glows below the constellation of Orion. Procyon, the brightest star of the constellation Canis Minor, the Little Dog, can be located at the lower left of Canis Major. By drawing an imaginary line among the bright stars of these constellations, an equilateral triangle will be formed called the Winter Triangle as shown here:
Also, flying high in this month’s sky is the mythical winged horse Pegasus. Although one of the largest constellations in area, it boasts no bright stars. Its most noticeable star pattern is the Great Square of Pegasus: four second magnitude stars marking the body of the horse. Ironically, the brightest of those stars, Alpheratz, isn’t even an official member of the Pegasus constellation, being part of the neighboring constellation Andromeda. The brightest star in Pegasus isn’t part of the Square: it is Enif, the Arabic word for “nose.” It marks the head of Pegasus, off to the west.
As you look further south, you can see Piscis Austrinus, the southern fish, with the only bright star in the region: Fomalhaut. Fomalhaut, which is 25 light-years from Earth, made headlines in 2008 as one of the first stars to observed to have a planet that was directly imaged with telescopes.
To the east of Fomalhaut is another huge dim constellation, Cetus the Whale, with the only other brightest star in the area, Deneb Kaitos, which means the tail of the whale. Cetus also contains the variable star Mira. Currently this star is too faint to be visible with the naked eye, but over the next few months it will start climbing in brightness until it becomes one of the brightest stars in this constellation.
Normally this sea world is a dim and mysterious place, with only one bright star, Fomalhaut. But this year it is enlivened by a visit from the giant planet Jupiter, right on the border between Pisces and Aquarius.
The tight grouping of Venus, Mars, Saturn, and Spica ends its spectacular run this month. All four are low in the western sky at nightfall as September begins, but Saturn drops from sight early in the month. Mars and Venus are still in the sky by month’s end, but they shine for only a little while before dropping below the horizon. By that time, however, the night sky’s next-brightest object, the planet Jupiter, is climbing skyward in the east, and will shine brilliantly throughout the night.
Mercury will shine brightly at magnitude -1 as it reaches its greatest elongation west on September 20 (18° from the Sun). For early risers, Mercury makes its best morning appearance of the year on the second week of September. Look in the constellation of Leo the Lion near his lower foot star, Rho Leonis. The two objects are 20 arcminutes apart on September 16 and 17.
Venus continues to be prominent in the evening sky, though also low for northern hemisphere observers, at around magnitude -4. The crescent Moon, less than 3° away on September 11 will make an attractive pairing. On the 24th, Venus will reach its peak magnitude of -4.6.
Mars is now shining very low in the evening twilight sky. This month +1.5 magnitude Mars starts a few degrees to the upper right of brilliant Venus. Though the planets will slowly move apart they will stay within 7° of each other all month long.On September 11, the Moon will pass with 5° of the planet.
Giant planet Jupiter is now top target for planetary observers, dominating the night sky and rising in the east as it is getting dark at a bright magnitude of -2.9 in Pisces. The planet is putting on a show for those with reasonable sized telescopes, having lost one of its prominent dark belts and with its two red spots in close proximity. On the 21st, Jupiter will be at opposition,means it will be visible all night long, rising in the evening, reaching its highest elevation around midnight and setting during dawn.
Saturn is located low in the west during evening twilight. By month’s end the +1.0 magnitude planet will be too close to the Sun to be seen easily by most observers. On September 9,the Moon will be within 7° of Saturn.
Uranus will lie within one degree of Jupiter in Pisces between September 12 and 25, making the giant planet a good signpost to finding its more distant cousin. On the 22nd, it will also be at opposition. If given a clear dark sky and no moonlight, it can be spotted with the unaided eye at magnitude of 5.7.
Neptune will be found among the background stars of the constellation Capricornus, the Sea-Goat and will be standing 42 degrees above the east southeastern horizon at around 7:00 PM (PST) on the 19th of the month. A modest size telescope will be needed to observe the bluish planet.
Sporadic meteors are not part of any known meteor shower. They represent the background flux of meteors. Except for the few days per year when a major shower is active, most meteors that are observed are Sporadics. This is especially true for meteors observed during the evening. During September, 10-16 or so Sporadic meteors can be observed per hour from a dark moonless sky.
Minor Meteor Showers
Minor showers produce so few meteors that they are hard to notice above the background of regular meteors. Information on most of the minor showers will be provided on a weekly basis by Robert Lunsford’s Meteor Activity Outlook this month.
Additional information on these showers and other minor showers not included here can be found at the following sites: Wayne Hally’s and Mark Davis’s NAMN Notes, and the International Meteor Organization’s 2010 Meteor Shower Calendar.
Just recently, a friend shared an article from Manila Bulletin’s website titled “36 hours of darkness in US likely on October 17”. I read it and had an impression that this could be another nonsense rumor like the Mars Hoax , based on my own knowledge of these things. However, the writer claimed that the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) said that this event “may partially hold true“.
Quoting the original article, it says
Online and text rumors claiming that the sun will rise continuously for 36 hours on October 17, 2010 in some parts of the world and leave the United States in darkness for 36 hours may partially hold true, an official of the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (Pagasa) said on Wednesday.
The report spreading through e-mails and text messages noted that this “coming October 17, 2010, the sun will rise continuously for 36 hours (1.5 days). During this time, the American countries will be dark for 1.5 days. It will convert three days into two big days. It will happen once in 2,400 yrs.”
I did my own research on this topic to know more and I learned that the same article with the same author, Ellalyn de Vera, was also featured in Yahoo News – Philippines and in another local newspaper, Tempo. Other than these, only a few websites had discussions which debunked this topic. Following are some of them:
“The further north you go, the longer the days. This may be true near the arctic circle, but not for the US, other than Alaska. And it certainly does not happen just over two to three days. Arctic days and nights are gradual things, lengthening and shortening over the course of a year. For it to happen just for the day, the Earth would need to slow down its rate of spin. Not possible for a body as massive as the Earth, without destroying itself as the energy from angular momentum changes so abruptly.” (This is one of the best logical explanations I found.)
Most of the websites above clearly said that this “hoax” originated in India and circulated in emails and text messages since 2008.
To further confirm the information contained in the article, I decided to visit the PAGASA Astronomical Observatory in U.P. Diliman to look for Engr. Dario dela Cruz, officer-in-charge of the PAGASA space sciences and astronomy section. Unfortunately, he was not there during that time so I just talked to Sir Mario, the head of the Observatory about the article.
I showed Sir Mario a copy which I printed from the Internet and he told me that it was the first time he had seen the news report.
We spent a few minutes talking. There were several important points raised during our discussion which I will list down here:
(1) Engr. dela Cruz’s statement below is true.
“After we experience the equinox during September, countries located in the Southern Hemisphere begin to observe longer days, as against those in Northern Hemisphere that observe longer nights, which include the northernmost part of the United States.
Starting September 24, there is a gradual decrease in the number of hours of nighttime as we go below the latitude. Countries located above 66.5 degrees are those that only experience a whole day of darkness.”
(2) However, if the “36 Hours of Darkness” will happen, the possibility of its occurrence will just be limited to the northernmost or southernmost part of the globe like the north of the Arctic Circle or south of the Antarctic Circle. (see diagram below for visualization)
(3) Currently, the most number of hours in which the sun would not set (also called the Midnight Sun) or rise is only for 24 hours and it happens mostly north of the Arctic Circle and south of the Antarctic Circle, never in any part of America which is located at lower latitudes.
(4) This event, the Midnight sun, is a natural phenomenon and it happens every year, not just every 2,400 yrs as was claimed in the article.
(5) There is still no scientific evidence based on data and computations that the 36 hours of darkness is likely to occur. The basis for the expected date October 17, 2010 wherein it was said to happen was still unknown to them.
(6) If this was to happen, it was only logical that the event should fall near solstices, and not near equinoxes.(September Equinox this year)
So based on Sir Mario’s explanations, the claim in the article about having “36 hours of Darkness” is more likely just a misinterpretation or simply a HOAX.
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Equinox – occurs twice a year, when the tilt of the Earth’s axis is inclined neither away from nor towards the Sun. The term equinox can also be used in a broader sense, meaning the date when such a passage happens. The name “equinox” is derived from the Latin aequus (equal) and nox (night), because around the equinox, the night and day are approximately equally long. This year, equinox falls on March 20 and September 23.
Solstice – either of two times of the year when the sun is at its greatest distance from the celestial equator. The summer solstice in the Northern Hemisphere occurs about June 21, when the sun is in the zenith at the tropic of Cancer; the winter solstice occurs about December 21, when the sun is over the tropic of Capricorn. The summer solstice is the longest day of the year and the winter solstice is the shortest.
image credit: Google images